I am needing to do a cost benefit analysis for a project. I would like
to add a computer to my small business so that my two employees do not
have to share. I have no idea where to start on this. Is there a good
template that I can download, or can somebody help me set one up.

No need for a cost-benefit analysis.  The other factors, e.g.  privacy
for your employees, access to the computer without having to wait for
the other employee to get off, having a second computer in case the
first goes down, and the negligible cost for a computer (under $1,000)
all would say get the second computer.